Zandvlei Trust

Draft minutes for the Meeting on 29 May 2013.

CAPE Estuaries Programme: Implementation of the Estuary Management Plan (EMP) for the Zandvlei Estuary, Muizenberg, Cape Town.


Minutes of the 8th Meeting of the Zandvlei Estuary Management Forum (ZEMF): 18:00, 29th May, 2013, Zandvlei Sports Club/Yacht Club.   ZEMF 8 Minutes ver A 20130613.

Summary of follow-up actions.

Action. Resposible Person. Target Date.
Meeting/site visit to be arranged between DEA & DP and W & S re sewage spills DEA & DP June, 2013.
ICompilation of a list of health incidents linked to recreational activity in the vlei. SF/LJ July, 2013.
Obtain information on legal action being taken by Zeekoevlei residents regarding a sewage leak. DaG June, 2013.
Obtain clarification on the status of Contingency Plan from DG. SF/LJ July, 2013.
Proposal for financial support for the Forum - follow up with Councillor D’Alton and Biodiversity Management Branch. Sandra Fowkes June, 2013.
Follow-up on letter to Mr. Asmal re pondweed. Sandra Fowkes June, 2013.
Weekly harvesting reports  Josh Gericke Ongoing.
Press release on fishing signage/by-law/permits etc. Arne Purves & Josh Gericke June, 2013.
Replacement of telephone numbers on sign boards. Josh Gericke June, 2013.
Further review of recommendations of Pondweed TWG in light of comments provided. Ken Findlay (TWG) June / July 2013.
Clarify what the delay is in getting the City Nature Reserves declared under the PAA. Pierre de Villiers July, 2013.
Determine origin and status of the document: TOR for PAAC discussed at ZEMF 8. Sandra Fowkes June, 2013.

Note - Given that the next meeting of the Forum is only in August, feedback on actions scheduled
for June should be provided to the Chair once they have been completed.


 Minutes.

1. Welcome and introductions
Welcome and introductions
Participants were welcomed to the meeting by Sandra Fowkes, the Chair of the Forum.. A list of participants can be found at Annex 1 and a copy of the Agenda at Annex 2.
Apologies - were received from Councillor D’Alton, Martin Thompson, Candice Haskins, Darryl Colenbrander, John Fowkes and Ken Findlay.

In response to the Chair’s request to Members to identify positive developments at Zandvlei since the last meeting, the following were put forward:

  • There had been a good response from the Reserve staff to the IYC’S requests regarding pondweed harvesting (DaG);
  • There had been a good CWAC count (increased bird numbers and species) (GL);
  • There had been a successful fish trek also showing increased numbers and species (JG);
  • There are now 3 CPUT students doing projects at Zandvlei, one on alien fish/plant species and two on pollution-related issues (DW);
  • There have been no further sewage spills and there are more government departments attending meetings (PdV);
  • Fishermen are also catching more fish – including a 35cm leervis (CV & GP);
  • The City proactively communicated with IYC with regard to adjusting the mouth opening schedule to allow for a recent yachting event (SF).

2. Adoption of the Minutes of the 7th ZEMF Meeting
The minutes were adopted without any changes. Adoption was proposed by GL, seconded by CV.

3. Matters arising from the Minutes of the 7th ZEMF Meeting

3.1 Meeting on Sewage Spills

At ZEMF 6 it had been agreed that a meeting and site visit would be arranged with officials from DEA & DP and the Water and Sanitation Department of the CoCT. LJ reported that she had followed up on this at the request of PdV and had circulated an e-mail proposing possible dates. However, DEA & DP had been unable to make either date and had also not come back with alternative dates. LJ subsequently discussed the matter with Cathy Bill from the Pollution Division of DEA & DP and it had been agreed that her staff would arrange the meeting directly with Water & Sanitation and would also include a representative from Environmental Health in the City. During the discussion with DEA & DP, emphasis was placed on concerns over the lack of communication around sewage spills and the potential health implications for recreational users of the vlei.

LJ also noted that she had been able to locate the monthly reports of Water & Sanitation to the Portfolio Committee for the months December, 2012 through March, 2013, as well as a 5-year summary report. These reports cover spills from pump stations rather than those resulting from blockages in the reticulation system and are summarised in Annex 3. Based on this information, the pump stations of greatest concern are Military Road, the Marina, and Raapkraal.

There was then further discussion around the health concerns and lack of communication regarding spills. It was noted that there had been another spill in Military Road on the 18th of May. This was reported to the Chair by a resident who had seen it while driving along Military Road. He had reported it via the 086 # and it had been addressed by the following day. However, there had been absolutely no communication regarding the spill from Water and Sanitation. Even the Zandvlei Reserve Manager was unaware of it. At the same time, over the past few months a number of reports of health problems resulting from recreation on the vlei have been emerging, at least one of which resulted in the person being hospitalised. DW expressed particular concern about this, noting that the Sea Cadets swim in the vlei on a regular (weekly) basis. It was agreed that a dossier should be compiled with details of these health incidents.

In the context of concerns around the ongoing lack of communication relating to sewage spills it was agreed that ZEMF should continue to:

  • Encourage people to report spills to the 086# and to get a reference # for such calls so that where there was no follow-up action problems could be identified;
  • Put pressure on Water & Sanitation to inform the Reserve Manager of such spills, and the Reserve Manager, in turn, to inform the representatives of the recreational user groups (IYC, PCC and Sea Cadets).

It was noted that reporting of sewage spills is required by the Contingency Plan, but it is not clear whether this plan has, as yet, been formally adopted. Clarification on this should be obtained from Dalton Gibbs.

The question was then raised as to what recourse the public has, especially around health incidents arising as a consequence of the City’s failure to communicate information on sewage spills. Both legal recourse and the use of the media were proposed, and DaG noted that the residents of Zeekoevlei are currently taking Council to court because of a leak from the sewerage works into that vlei. Further information on this action would be obtained.

3.2 Proposal for financial support
No comments had been provided to the Chair, but the proposal had nevertheless been sent to Councillor D’Alton for consideration. PdV noted that municipalities in other areas are already providing support to the forums.

3.3 Letter to Mr. Asmal re Pondweed Issues
The Chair reported that she had not received a response from Mr. Asmal as yet and agreed to follow up with him.

3.4 Press Release on Fishing Signage/By-law/Permits
As neither of the responsible officials were present at the meeting, it was agreed that this item be carried over.

4. 4. Pondweed Management
The Pondweed TWG had been reconvened by Ken Findlay on the 23rd May and had produced a revised set of recommendations on Pondweed Management. In the absence of KF, the Chair presented the revised recommendations to the meeting and during a lengthy discussion, some further revisions were proposed. In addition, GL and DW agreed to provide input on a couple of points. The points raised in the Forum meeting, as well as the input from GL and DW, are captured as footnotes in the version of the document which is appended to this report as Annex 4.

Another proposal which had been discussed at the Pondweed TWG meeting, but which was not included in the recommendations, was to uproot and remove pondweed in certain parts of the vlei by dragging a chain across the bottom. The TWG were aware of potential problems with such an initiative, in particular the disturbance of the sediments and resulting release of toxins and/or nutrients into the water column, but felt it could be attempted in a small area on an experimental basis on an outgoing tide i.e. when the mouth was open.
This prompted a discussion during which the following points were raised:

  • It would destabilise the bottom sediments which is very risky if the sediments contain toxic material;
  • GP referred to a recent incident where a relatively small disturbance in the Keysers River had caused a fish kill. This is an indication of what might happen;
  • The sediment sampling being undertaken by Brent Newman of the CSIR could give us some indication of the contaminants in the sediments, but these results will only be available next year;
  • DaG reported that some junior sailors had pulled out rooted pondweed in the basin near the IYC about 1 year ago and it is now as thick as was originally.

These concerns, together with the comments on the document in Annex 4 need to be considered at the next meeting of the TWG.

5.  Any Other Business

5.1 Update on Legal Status and TOR for PAAC

As far as could be ascertained, the documents declaring Zandvlei (and a number of other nature reserves in the City) as Nature Reserves under the Protected Areas Act are still lying in the Premier’s Office awaiting signature.

There was then some discussion on the Terms of Reference for the Establishment of a Protected Area Advisory Committee (PAAC). Based on the document at hand, it was agreed that the TOR are similar to those of ZEMF. Since they also provide for logistical and resource support to the PAAC, it would seem to make sense for ZEMF to be re-constituted as the PAAC for Zandvlei once the legal basis is in place. However, there was some concern as to the status of the TOR in particular, have they been formally adopted by the City, or was this a draft for comment.

On the other hand, the recent gazetting of the final National Estuary Management Protocol (NEMP) appears to strengthen the argument for ZEMF to become a Protected Area Advisory Committee. With respect to institutional structures and arrangements, the NEMP states:

“Effective institutional structures and arrangements are crucial support elements for the successful implementation and coordination of actions in terms of the Protocol and the subsequent estuary management plans. Chapter 5 of the ICM Act details the institutional arrangements that would, once implemented, contribute to cooperative coastal governance in South Africa. These arrangements are made at national, provincial and municipal levels and the embodiment of cooperative coastal governance is vested in coastal committees. No new institutional arrangements are proposed by the Protocol. The Provincial and Municipal coastal committees shall serve as the forums for monitoring the implementation of EMPs and reporting of progress and achievements related to estuarine management. Any existing and/or planned individual estuary forums can be regarded as informal additional advisory bodies for facilitating the implementation of the project plans identified in the EMPs and to foster continuous stakeholder engagement.”

Despite this, according to PdV, the Provincial and Municipal Coastal Committees themselves can appoint formal advisory committees. However, Cape Town does not as yet have a Coastal Committee in place.

5.2 AGM

It had been previously agreed that before an AGM was called, there should be clarity on the legal status and funding arrangements for ZEMF. Since neither of these criteria have yet been met, no date was set for the AGM. It was, however, agreed that regardless of the above, an AGM must be held before the end of the year, tentatively September or October.

5.3 Study on Coral Worm

LJ reported that Kirsty McQuaid had completed her MSc thesis on the coral worm, Ficopomatus enigmaticus. The thesis supports the contention that it is an alien species, and one the main findings is that “..the standing stock of F. enigmaticus in the Marina da Gama has increased from 11.80 t in 1989 to 50.03 t in 2012 due both to an increase in the total area colonised by F. enigmaticus, and the dry mass of worm per m2.”

6. Dates and focus for next meeting/s

The next meeting is provisionally scheduled for the 21st of August, 2013 at 13:30, but may need to be changed to the 28th August. Members will be advised closer to the time.


Annex 1.

List of Attendees at the 6th Meeting of the ZEMF on 29th May 2013.

Organisation Name ABV Rep/Alt/Ind

ZEMF Chair

Sandra Fowkes

SF Chair
CapeNature  Pierre de Villiers PdV Rep
CoCT (BMB) Dalton Gibbs DaG Alt
Sea Cadets David Walker DW Rep
Cape Piscatorial Society Garnet Prince GP Rep
Cape Bird Club Felicity Ellmore FE Alt
Cape Bird Club Gavin Lawson GL Rep
Fishing fraternity Case Veugelers Rep Rep
C & EC Lynn Jackson Consultant Consultant

 


Annex 2.

CAPE Estuaries Programme: Facilitation of the Estuary Management Plan (EMP) for the Zandvlei Estuary, 
Muizenberg, Cape Town

8th Meeting of the Zandvlei Estuary Management Forum (ZEMF)
18:00 – 20:00 : 29th May, 2013 
Zandvlei Sports Club (Yacht Club)

DRAFT AGENDA

Item
1. Welcome and introductions, apologies etc
2. Adoption of Minutes of ZEMF 7
3. Matters arising from the 7th ZEMF Meeting
3.1 Site visit to assess sewage spills (PdV/LJ)
3.2 Proposal for financial support for Secretariat function (SF)
3.3 Letter to Mr. Asmal re Pondweed Issues (SF)
3.4 Press release on fishing signage/by-law/permits etc (JG/AP)
4. Pondweed ManagementReport back from Pondweed TWG
5. Any Other Business
5.1 Update on legal status & discussion of ZEMF becoming Estuary Nature Reserve Advisory body (please read attached Terms of Reference for Advisory bodies)
5.2 AGM
6. Dates and focus for next meetings in 2013.


Annex 3.

RECORD OF SEWAGE SPILLS FROM PUMP STATIONS AT ZANDVLEI.

Date. Location. Severity.

2013

10/02/2013 Bergvliet Minor
18/02/2013 Plumstead (Timour Hall PS) Minor
20/02/2013 Military Road, Retreat Medium (Sand River PS into Langevlei Canal)
21/02/2013 Military Road, Retreat Severe (Sand River PS into Langevlei Canal - treated by Biosystems SA)

2012

February Raapkraal, Kirstenhof Severe spilled into Westlake River & reached Zandvlei.
2009
21/04/2009 Retreat Main Minor (into detention pond)
30/09/2009 Retreat Main Minor (into detention pond)
2008
01/02/.2008 Military Road, Retreat,
Uxbridge Road,
Marina da Gama 4 & 9 + others as a result of a power outage.
Minor (into Keyser’s River & various stormwater drains)
17/05/2008 Military Road, Retreat Level 1 (into Langevlei Canal)
20/06/2008 Marina 4 (Spearhead Quay) Level 2 (minor, but into vlei)
20/08/2008 Retreat Main (Seawinds) Level 1 (into bush?)
2007
17/01/2007 Retreat Main (Vrygrond) Low (retention pond)
19/09/2007 Military Road, Retreat Medium (Langevlei Canal)
28/09/2007 Military Road, Retreat Medium (Langevlei Canal)

 


Annex 4.

Comments on Draft final Report of the Pondweed TWG on Pondweed Management
This draft was prepared by Ken Findlay, Sandra Fowkes, Lynn Jackson and Joshua Gericke at a meeting of the Pondweed TWG on 23 May 2013. Apologies were received from Damian Gibbs, Garnet Prince and David Walker.

1. Introduction
The pondweed, Potamogeton pectinatus, occurs naturally in Zandvlei and is an important component of the ecosystem, providing habitat for a variety of organisms, reducing nutrient loading and oxygenating the water. However, as a result of the high nutrient conditions, pondweed has been a problem in Zandvlei for many years, at times forming dense mats which restrict boating activities, exacerbate flooding, limiting light penetration, restricting current flow and thus increasing stagnation (3), and, when they start to decompose, causing unpleasant odours and raising nutrient levels. The pondweed in Zandvlei has therefore been managed since 1976 by harvesting it using a mechanical harvester. Although the harvesting has been successful at times, there have been occasions when over-harvesting has led to collapses in the population (Harding, 1999) while at other times the excessive levels of pondweed have hindered recreational use of the estuary, created nuisance conditions and impacted on property values in the area. This situation continues despite the development of harvesting guidelines for the City by Southern Waters in 1999.

(3) There was concern over some of these additions – particularly the point about restricting current flow and increasing stagnation. PdV felt that the main issue was the suitability of the area for recreational activities and that greater emphasis should be placed on the need to find a balance between recreational and ecological needs. (DW to provide input here).

2. Protocol for Pondweed Management
The TWG therefore recommends that a new protocol for the management of pondweed in Zandvlei be developed based on the following:

2.1. Desired outcomes of pondweed management
Given the ecological importance of pondweed, the overall objective of management efforts must be to achieve a sustainable level of pondweed in the system while at the same time preventing the development of conditions which affect the recreational use of the estuary, are a nuisance to residents and affect property values in the area. In other words, the pondweed levels must be sufficient to maintain the ecosystem services it normally provides (including habitat provision, oxygenation and nutrient sink services).

In addition to its ecological functions, Zandvlei has significant aesthetic and recreational value and is the primary attraction for the majority of residents in the area. It is used for formal and informal recreational activities - including inter alia bird-watching, picnicking, yachting, canoeing, boardsailing, kite-boarding and swimming - as well as a number of events such as the Rotary annual Dragonboat racing fundraiser, Scout regattas and annual Kontiki event, and has recently been used by international canoeing teams for training purposes.

It thus has a variety of socio-economic benefits for the area and needs to be managed accordingly. This includes keeping specified areas clear of pondweed, other nuisance plants and debris which tends to accumulate in some areas, especially the blind canals of the Marina. It should be noted that pondweed management treats the system symptomatically only in that the causal factors of the extensive pondweed growth (the elevated nutrient loads within the system arising from its location within an urban setting) are not addressed within this plan.

The specific proposed outcomes of pondweed management therefore include:

  • The areas set aside for recreational activities (see Figure 1) to be kept clear of pondweed to a depth of 0.5m for all canals in the Marina, and to a maximum depth of 1.5m (5) in the main body of the vlei, provided that harvesting in all areas should not go closer than 2m from the banks (6) ; Note that the weed harvester can only cut to a depth of about one meter, but such cutting is very slow.
  • A healthy pondweed reserve of 30% of the estuary area (see Figure 1) should be maintained;
  • An improved understanding of pondweed dynamics in Zandvlei.
  • The implementation of a cutting schedule that is synchronised with the mouth opening schedule so that maximal depth cutting can be carried out in the main vlei when the water depth is at its shallowest.
  • The ensuring of adequate flow regimes within the system so that stagnation does not occur.(7)

2.2. Achieving the Outcomes
The harvesting guidelines developed in 1999 by Southern Waters recommended a harvesting frequency of 12 times a year in the recreational areas. It is acknowledged that this frequency is speculative (8) and a more objective frequency should be determined through a monitoring programme, which given the inter-annual variation in pondweed growth should be carried out as a multi-year programme.(9)

(4) It was suggested that text be added to the effect that the nutrient problem needs to be addressed in the Catchment. Also noted that it is touched on in the EMP.
(5) It was proposed that this bullet point be amalgamated with the one on synchronisation since these are inter-related.
(6) It was reported that this condition is incorporated into the Agreements of Sale for Marina properties (GL).
(7) It order to give effect to this, node points should be identified.
(8) Wording should be revisited – Harding did recommend monitoring.
(9) Recommendations should make a single proposal – suggested that it should be a rotational schedule which takes into account various factors including recreational events, tides etc. The information of events should be provided well before the start of any year so that it can be included in the planning process. Any deviations should be agreed through the TWG.

Two proposed models for the management of pondweed in the Zandvlei system were identified:

2.2.1. Rotational Schedule
This model proposes that pondweed be harvested on a strict rotational schedule aimed at ensuring that a) pondweed biomass does not get out of control and b) acute management intervention be required when it does so.(10)
During the period that harvesting was undertaken by City Parks, they worked on a harvesting frequency of 7 times annually (twice in Summer, twice in Autumn, once in Winter and twice in Spring). This approach is generally regarded as having been successful for those periods when these targets were met (i.e. when the harvester was able to complete the required work).

In order to achieve the outcomes described above, it is therefore recommended:

  • For at least the next year, all the areas to be harvested should be cut 7 times; (11)
  • 20% of the pondweed reserve should be harvested once during the course of each year. Such harvesting should be carefully monitored; (12)
  • The harvesting should be implemented according to a reasonably strict rotational schedule (see below) and should be monitored so as to be able to assess the effectiveness of these proposals and to provide a basis for any future adjustments;
  • Clearing within 2m from the banks should be limited to securing access to the central channel and must be undertaken by residents. Requests from residents to use the harvester to cut pondweed within this area should not be entertained;
  • Projects on the monitoring and assessment of pondweed harvesting and growth should be undertaken in collaboration with CPUT. An initial review of the frequency of coots within the monthly / quarterly CWAC counts may provide some historic data as proxy for pondweed biomass.(13)

2.3. On Demand Harvesting
This model proposes that pondweed be harvested on a demand basis to address the criteria of water flow, ecological function and recreational needs. Under this model recreational users may apply for clearing of particular areas, but such applications need to be made as far in advance of particular events as possible. Clearing should however be carried out close to the required dates to ensure that no re-growth has occurred.

In reality a combination of these two models would be the best strategy.

(10) Prior to the compilation of the schedule, the TWG should agree on spatial and temporal priorities which should then also be the basis of any deviations from the schedule.
(11) This is proposed as a trial period – if successful, it would continue on this basis.
(12) There were some objections to this with concerns being raised about over-harvesting. However, it was noted that this was agreed some time back and is considered necessary to promote regeneration of the pondweed in the reserve areas. The question was raised as to whether there is any science to back this up. DW to provide input.
(13) Alternative text proposed by GL reads: An initial review of nest building activity by Coot and or Great Crested Grebe as an indicator, at the monthly MyBirdPatch and quarterly CWAC counts will provide some data as proxy for the presence of pondweed biomass. GL 30/05/2013.
(14) See footnote 7 above.

2.4. Challenges of these management models

2.4.1. Harvesting Requirements and Demand
Based on the map in Figure 1, approximately 61.5 ha of Zandvlei (recreational areas including the Marina canals) need to be cut 7 times per year. In addition, 20% of the pondweed reserve area should be cut once a year. The reserve area is approximately 28 ha, which means that 5.6 ha would need to be cut every year. This means that a total of 436.1 ha need to be cut/year.

2.4.2. Current Harvesting Service Supply
Assuming a cutting rate of 0.14ha/hour (Southern Waters), this means that 3115 machine hours/year are required to do the job. In addition, provision needs to be made for maintenance and downtime as a result of weather conditions and machine failure. Based on records for the past year, the average number of operational hours achieved by the harvesting machine per day was between 5 and 6 – for periods when the machine was actually functional. However, these records also indicate a downtime of around 20% of the time. On this basis, and assuming a 5-day week, the current complement of 1 harvesting machine and a single driver/operator delivers less than half of the hours required to complete the job. Even if the operating hours are increased to 7 hours/day and the downtime reduced to 10%, the number of hours available could only be raised to a little over half of those required. Realistically then, the only option available to meet the required schedule is to:

A. Make a second machine and driver available. The second weed harvester was removed to Little Princess Vlei (15) in Month /Year with little consultation to Zandvlei users. It is recommended that the rationale for this transfer of this resource be reviewed including: (16)

  • The size, extent and biomass of invasive aquatic plant material in the Little Princess Vlei system (where the majority of material believed to be parrot’s feather)
  • The efficacy of cutting parrot’s feather with the transferred weed harvester.
  • The use of the Little Princess Vlei system as a recreational facility including its comparable value to Zandvlei as a training facility for sporting disciplines at an international level,
  • The use of alternative management regimes such as bio-control in the eradication of parrot’s feather,(17) and
  • A review of the purchase agreement of the harvester as it possibly may have been originally purchased for the Marina da Gama.(18)

(15) This transfer was effected as part of the transfer of the responsibility for harvesting in Zandvlei from City Parks to BMB. City Parks retained responsibility for Little Princess Vlei and use the 2nd harvester there.
(16) Suggest this be reworded – it was noted that the machine has in fact been removing pondweed in Little Princess Vlei in recent weeks.
(17) To be discussed with the ISU.

B. have a relief driver so that harvesting is not affected by driver illness and, when necessary, can be extended into weekends or after hours (should the weather be conducive);

C. reduce downtime to 5% by improving maintenance and addressing other operational issues.(19) Recent records indicate that there are major logistical problems with the machine breaking down on a regular basis, with downtime reaching around 20% of the operational time. Although the machines are quite old, the static items of the harvesters should have a lifespan of 50 years, and according to the specs should be able to do 10 – 12 hours/day. While it was suggested that the problems arose primarily from a combination of the fact that some of the parts have been incorrectly engineered and from poor maintenance and operating errors, these have to a large extent been remedied. These problems included:

  • The cutting blades are incorrectly adjusted - these have been adjusted;
  • The cutting blades used are not appropriate for cutting pondweed. To be efficient, the blades which should be used are those which are normally used to cut rice (which are designed to operate in aquatic conditions) rather than grain/grass which require low levels of moisture to operate effectively. There is a 10-30% increase in cutting efficiency if the correct blades are used – the correct blades are being sourced through local maunufacture.
  • Incorrect cutting blades cause weed to be ripped out rather than cut causing undue load on the harvester’s front mechanism - this will be addressed through acquisition of the correct blades
  • Incorrect forward speed of the harvester in relation to the speed of the cutting blades – causes some of the weed to be ripped out and float away under the machine especially when done in conjunction with the incorrect blades – this has been corrected.
    In addition, there are a limited number of trained drivers/operators.

2.5. Cutting Management Strategy
In order to overcome the above challenges it is recommended that:

  • The second machine should be returned to Zandvlei on a permanent basis as each transfer costs R60 000 return in terms of a crane and special flatbed trailer;
  • The previous Pondweed TWG recommendations of the current Zandvlei machine being re-engineered and maintained to the required specifications and that the City should make provision for the holding of critical spares to reduce downtime, have largely been addressed;(20)
  • A GPS should be installed on the machine to monitor the time and locations at which the harvester is operating;
  •  Additional resources should be provided to Biodiversity Management so that additional drivers can be trained with a view to increasing the efficiency of machine utilisation (increased number of hours/day) and prevent downtime as a result of illness;
  • The possibility of utilising barges to transport cut material from the harvester to the shore should be investigated with a view to increasing the time available for cutting. Such barges should be designed to be able to collect floating rafts of cut weed when these occur;
  • The possibility of using Coastcare teams (or other EPWP resources) to supplement the harvesting programme should be investigated;(21)
  • Proper provision must be made to ensure that harvested material is removed from the banks of the estuary on a timeous basis.
  • A Robust framework for monitoring and analyses of the efficacy of the harvesting schedule needs to be in place; (22)
  • Weed harvesting of the main vlei needs to be synchronised with mouth openings to maximise depth cutting at low water levels.
  • (23)

(18) It was noted that this 2nd machine is in a bad state and it was suggested that Anglo be approached to provide a new machine.
(19) Need to reword this paragraph to properly reflect the fact that many of the problems have been addressed and rather highlight the remaining ones.
(20) See footnote 17.
(21) Coastcare is more likely to complement the harvesting through removal of other weeds and litter.
(22) Monitoring proposals should be included into these recommendations. In addition to the proposals under 2.2.1 (on birds), it was suggested that there should be fixed point photographic monitoring on a monthly basis.
(23) An additional proposal was to increase the amount of sea water intrusion into the vlei by, for example, removing the sewer line across the mouth so that the weir can be lowered further.


Annex 5.

List of Commonly Used Acronyms

BMB  Biodiversity Management Branch
CoCT City of Cape Town
CPUT Cape Peninsula University of Technology
CWAC Co-ordinated Waterbird Annual Count
DEA & DP Department of Environment Affairs and Development Planning
EMP Estuary Management Plan
IYC Imperial Yacht Club
NEMPA National Environmental Management: Protected Areas Act
PAAC Protected Area Advisory Committee
PCC Provincial Coastal Committee
SAPS South African Police Services
TWG Technical Working Group
W & S Water and Sanitation Department
ZEMF Zandvlei Estuary Management Forum

 


                                                                                                                                                   

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